It’s not just the little guys that are struggling to make money from foreign exchange. The big boys aren’t having much luck either, if banks’ financial statements are anything to go by.

In their second-quarter results out Tuesday, currency-trading heavyweights Deutsche Bank and UBS both indicated that revenues from foreign-exchange trading fell in the three months to June.

Banks rarely break out revenue from currency trading alone and instead report performance for fixed income, currencies and commodities. However, UBS was clear about how its all-important currencies business fared last quarter.

UBS, which according to the annual benchmark Euromoney poll is the third-largest currency bank in the world, said revenues in its foreign-exchange business were lower in the second quarter compared with the same period in 2010.

“The exceptional volatility seen in the second quarter of 2010 did not recur, reducing the opportunity to capture spreads,” it explained.

Deutsche Bank, crowned the world’s biggest currency-dealing bank for seven years on the trot, was similarly downbeat.

“What do I think of Bob Diamond? I’m not sure I can say without swearing,” said a man in a knitted hat who identified himself as Magoo.

Behind him, outside the Barclays headquarters in Canada Square, 30 or so protesters were chanting “Shame on you!” at a group of bankers who had gathered in the lobby to watch from behind the glass.

Tuesday afternoon, the UK Uncut protest group targeted the financial services industry with small demonstrations outside several offices around Canary Wharf.

The event, which was billed as an “official tour” of the banks, accountancy firms and law firms behind the financial crisis, was raucous but non-violent and the dozens of police in attendance had little to concern them.

Financial workers on their way home seemed bemused, rather than threatened by the protests, which were ostensibly about tax avoidance but took in a gamut of financial misdeeds, including bonuses, credit derivatives and fraud.

“There aren’t many of them are there?” said a passing banker of the protesters.

As the crowd gathered outside Citigroup’s London headquarters, bank employees on the first floor peered out of the window, one smiling as he nonchalantly bounced a rugby ball on a desk.

Many of the protesters were teachers from local schools facing cuts, but there were also students and employees from a local supermarket.